Al-Kāfi - Volume 4 > The First Thing of Lands that Allah Created Was the Site of the House and How Was What He First Created
Hadith #6

6ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنْ حَمَّادِ بْنِ عِيسَى عَنْ أَبَانِ بْنِ عُثْمَانَ عَمَّنْ أَخْبَرَهُ عَنْ أَبِي جَعْفَرٍ (عَلَيْهِ السَّلاَم) قَالَ قُلْتُ لَهُ لِمَ سُمِّيَ الْبَيْتُ الْعَتِيقَ قَالَ هُوَ بَيْتٌ حُرٌّ عَتِيقٌ مِنَ النَّاسِ لَمْ يَمْلِكْهُ أَحَدٌ.

6. Ali ibn Ibrahim has narrated from his father from Hammad ibn ‘Isa from Aban ibn ‘Uthman from those whom he has mentioned (in his book) who has said the following: “I once asked abu Ja‘far, ‘Alayhi al-Salam, ‘Why is the House called free House?’ He (the Imam) replied, ’It is a free house. It is free from people; no one owns it.’”